/*
 * (C) Copyright 2013-2023, by Nikolay Ognyanov and Contributors.
 *
 * JGraphT : a free Java graph-theory library
 *
 * See the CONTRIBUTORS.md file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0, or the
 * GNU Lesser General Public License v2.1 or later
 * which is available at
 * http://www.gnu.org/licenses/old-licenses/lgpl-2.1-standalone.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR LGPL-2.1-or-later
 */
package org.jgrapht.alg.cycle;

import java.util.*;
import java.util.function.Consumer;

/**
 * A common interface for classes implementing algorithms for enumeration of the simple cycles of a
 * directed graph.
 *
 * @param <V> the vertex type.
 * @param <E> the edge type.
 *
 * @author Nikolay Ognyanov
 */
public interface DirectedSimpleCycles<V, E>
{
    /**
     * Find the simple cycles of the graph.
     *
     * @return The list of all simple cycles. Possibly empty but never {@code null}.
     */
    default List<List<V>> findSimpleCycles()
    {
        List<List<V>> result = new ArrayList<>();
        findSimpleCycles(result::add);
        return result;
    }

    /**
     * Find the simple cycles of the graph.
     *
     * @param consumer Consumer that will be called with each cycle found.
     */
    void findSimpleCycles(Consumer<List<V>> consumer);
}
